ML20062F882
| ML20062F882 | |
| Person / Time | |
|---|---|
| Site: | South Texas  |
| Issue date: | 11/15/1990 |
| From: | Collins S NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Hall D HOUSTON LIGHTING & POWER CO. |
| References | |
| NUDOCS 9011280242 | |
| Download: ML20062F882 (3) | |
See also: IR 05000498/1990028
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NW 151990
Docket Nos. 50-498/90-28
50-499/90-28
License Nos. NPF-76
NPF-80
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Houston Lighting & Power Company .
ATTN:
Donald P. Hall, Group
Vice President, Nuclear
P.O. Box 1700
Houston, Texas 77251
Gentlemen:
Thank you for your letter of October 17, 1990, in response to our letter
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and Notice of Violation dated September 18, 1990. We have reviewed your- reply
and find it responsive to the concerns raised in our Notice of Violation
(498/9028-01;499/9028-02). We will- review the implementation of your.
corrective actions during a future inspection to determine that full compliance
has been achieved and will be maintained.
Sincerely,.
/5/
. Samuel
J.. Collins, Director
Division of Reactor. Projects
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cc:
Houston Lighting & Power Company
ATTN:
M. A. McBurnett, Manager
Operations Support Licensing
P.O. Box 289
Wadsworth, Texas 77483
City of. Austin-
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Electric Utility Department
ATTN:
J. C. Lanier/M. B. Lee
P.O. Box 1088'
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Houston Lighting & Power Company
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City Public Service Board
ATTN:
R. J. Costello/M. T. Hardt
P.O. Box 1771-
San Antonio, Texas 78296
Newman & Holtzinger, P. C.
ATTN: Jack R. Newman, Esq.-
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1615 L Street, NW
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Washington, D.C.
20036
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Central Power and Light Company
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ATTN:
R. P. Verret/D. E. Ward
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P.O. Box 2121
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. Corpus Christi, Texas 78403
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INP0
Records Center
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1100_ Circle 75 Parkway .
Atlanta, Georgia- 30339-3064
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Mr. Joseph M. Hendrie
50 Bellport Lane.
Bellport, New York 11713
Bureau of Radiation Control
State of Texas
1101 West 49th Street
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Judge, Matagorda County
Matagorda County Courthouse
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1700 Seventh. Street
. Bay City, Texas 77414
Licensing Representative
Houston Lighting & Power Company
Suite 610
Three Metro Center
. Bethesda, Maryland 20814
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Houston- Lighting & Power :Conpany :
ATTN: Rufus S. Scott, Associate
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General Counsel
P.O. Box 61867
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Houston, Texas ~77208
bec to DMB (IE01) w/ licensee ltr.
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Houston Lighting & Power Company
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bec distrib. by RIV w/ licensee 1tr.:
R. D. Martin
Resident Inspector
SectionChief(DRP/D)
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MIS System
DRSS-FRPS
Lisa Shea, RM/ALF
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RIV File
R. Bachmann, OGC
RSTS Operator
Project Engineer (DRP/D).
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The Light
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c o mp a nysniji Texas Projn r.initie cenneiing sintion ).4. ps qs9 ' w
llouston Lighting & Power
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October 17, 1990
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ST HL.AE 3596
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Filo No.: C02 04-
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U. S. Nuclear Regulatory Commission
Attention: Document Control Desk
Vashington, DC
20555
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South Texas Project Electric Generating Station
-Unit 1
Response to Notice of Violations 9028 01 Land 19028 02
Failure to Follow Procedures.'for . Independent
Verification and Failure to Provide-Adecuate Accentance Criteria
Houston Lighting & Power has. reviewed the Notices of Violations issued
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as a result of NRC Inspection ' Report 90 028 dated September.18,1990, and.
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submits the attached responses,
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Notice of Violation 9028-01 occurred during the post trip recovery
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. effort for Unit 1 LER 90 006.. The response for' this violation is completely -
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covered in the attached LER 90 006 regarding a manual reactor trip due:to full'
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closure of'a WIV -during partial.' stroke testing.
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-If you should have any questions on this-matter, please contact
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Mr. A. K. Khosla-at (512) 972 7579 or myself at (512) 972 8530.
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M. A. McBurnett
Manager.
Nuclear. Licensing
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Attachment: Reply to Notices of Violations'9028 01.and 9028 02
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IIR 90 006 (South Texas, Unit 1)
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A Subsidiary oI Houston Industrics Incorporated
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ST.HL AE 3596
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llouston Lighting & Power Compan)-
File No.:002.04
South Text. Proj,ect Electric Generat og Stat.ion
Page 2
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cc:
Regional Administrator, Region IV
Rufus=S.= Scott
Nuclear Regulatory Commission
Associate General Counsel
(
611 Ryan Plaza Drive, Suite 1000
' Houston Lighting & Power Company .
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Arlington, TX 76011
P. O. Boi 61867
Houston, TX 77208
Coorge Dick, Project Manager
U.S. Nuclear Regulatory Commission
Washington, DC 20555
Records Center
v
1100 circle 75 Parkway
J. I. Tapia
Atlanta, GA 30339 3064
Senior Resident Inspector
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c/o U. S. Nuclear Regulatory
Dr. Joseph M.L Hendrie:
Commission
50 Bellport Lane-
P. O. Box 910~
Bellport, NY .11713
Bay City,1D( 77414
D. K. Lacker
,
J. R. Newman, Esquire
Bureau of Radiation Control
Newman & Holtzinger, P.C.
Texas Department of Health
1615 L Street, N.W.
1100 West 49th Street
Washington, DC -20036.
Austin, TX 78756 3189
R. P. Verret/D. E. Ward
Central Power 6 Light Company
P. O. Box 2121
Corpus Christi, TX 78403
J. C. Lanier/M. B. Lee
City of Austin
Electric Utility Department
P.O. Box 1088
Austin, TX 78767
R. J. Costello/M. T. Hardt
City Public Service Board
P. O. Box 1771
San Antonio, TX 78296
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-Revised 10/08/90
L4/NRC/
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Attachment
ST.HL.AE.3596
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Page 1 of 3
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1.
Statement if Violations:
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Failure to rollow Procedures for indenendent verificarica
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10 CPR Part $0, Appendix B Criterion V, requires, in part, that
activities affecting quality be accomplished in accordance with
documented instructions,
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Plant Procedure 1 PSP 03. AF.0001, Revision 6, " Auxiliary Feedwater
Pump 11 Inservice Test,' Step 5.13,1, states, 'CLost and LOCK Test
Line Isolation Valve AF0040 and initini Data sheet ( 2),' and Step
5.13.2, states 'As a (sic) independent verification have a second
individual verify Ar0040 is CLOSED And LOCKED and initial .Seta
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Sheet ( 2).
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Plant Procedure OPOP03 20 0004, Revision 11, ' Plant Conduct of
Operations,* Step 4.4.11, requires that independent verifications
shall be performed as prescribed by approved procedures or
' ,atructions in accordance with OPCP03.ZA.0010, " Plant Procedure
Compliance, Implementation, and Reviews '
Plant Procedure OPCP03.ZA.0010, Revision 11, * Plant Procedure
Compliance Implementation, Review,' Step 3.3.2.1, states that the
act v; performing the independent verificatio14 must be completely
separate and independent of the initial alignment, installation, or
verification.
Contrary to the above, on July 26, 1990, Steps 5.13.1 and 5.13.2 of
Plant Procedure 1 PSP 03 AF 0001 Revision 6, " Auxiliary Teedwater
Pump 11 Inservice Test," were performed concurrently and were,
therefore, not completely separate and independent.
This resulted
in a failure to detect that Test Line Isolation Valve AF0040 was
erroneously aligned in a locked open position.
This error was
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discovered following a reactor trip on August 6, 1970, when
auxiliary feedwater from Auxiliary Feedwater Pump No.11 was
circulated back to the auxiliary feedwater storage tank through the
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locked open valve instead 9f adding water to steam Generator A as
designed.
This is a Severity Level IV violation.
(Supplement I) (498/9028 01)
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Attachsent
ST.HL. AE. 3596
Page 2 of 3
2.
Failure to Prqvide Adecuate Acceptance Criteria
10 CFR Part 50, Appendix B, Criterion V requires, in rett, that
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procedures include appropriate acceptance criteria for determining
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that important activities have been satisfactorily accomplished,
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South Texas Project Technical Specifications, paragraph 6.8.1.a.
requires that procedures for activities identified in Appendix A of
Regulatory cuide 1.33, Revision 2, February 1978, be established,
implemented, and maintained.
Paragraph 3 to Regulatory Guide 1.33
requires that instructions for energizing, filling, venting,
draining, startup, shutdown, and changing modr.s of operation be
prepared for the chemical and volume control system (including
letdovn/ purification system).
Cor.trary to the above, on August 6. 1990, neither Operations
Procedure 1 POP 02.CV.0004, ' Chemical Voluue sad Control System
Subsystem,' Revision 8, or any administrativi procedure contained
adequate acceptance criteria for determining hat the activities to
place a mixed bed desineraliser in service had been satisfactorily
accomplished.
This is a Severity Level IV violation.
(Supplement 1) (498/9028 02)
II. Houston Limhting & Power Position:
1.
HL&P concurs that this violation occurred and attaches LER 90 006 in
response to this violation.
2.
HL&P concurs that this violation occurred.
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III. Reason for Violation
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See attached LF.R 90 006.
2.
The cause of this event was the procedure for placing the
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desineraliser in service did not requite a sample or provide an
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acceptance criteria for boron concentration prior to demineralizer
use. Additionally, the procedure for borating the desineralizer was
also less than adequate,
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Attachment
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ST.HL.AE 3596
Page 3 of 3
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IV.
Corrective Act!P.nt!
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See attached 12R 90 006, corrective actions 4 8.
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2a. The procedure for placing domineralizers ir service has been revised
to require domineralizer sampling and to specify acceptance criteria
when placing a demineralizer in service,
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b. The procedure for borating domineralizers has been changed to
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require the domineralizer outlet isolation valve to be closed for
the demineralizer that is not being flushed for sampling. This will
assure that only one demineralizer is flushed and sampled at a time.
The procedure has also been revised to ensure a representative
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sample is obtained from the demineralizer being borated.-
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V.
Date of Tull Como11ance:
H14P is in full compliance at this time.
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The Light
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c o m p a n y soutunn Projn: unuie Cennetleig station
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P. O. Bn FH Wadi.onh.Tu n 77o3
Houston LI htin & Power
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August 31,1995
ST.HL.AE.3547
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File No.: C26
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10CFR$0.73
U. S. Nuclear Regulatory Commission
Attention: Document Control Desk
20$$$
South Texas Project Electric Cenerating Station
Unit 1
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Docket No. STN $0 498
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Licensee Event Report 90 006 Regarding
a Manual Reactor Trip Due to Full closure of a
Teedveter Isolation Valve Durine Partial Stroke Testine
Pursuant to 10CTR$0.73, Houston Lighting & Power Company (HIAP) submits
the attached Licensee Event Report (1.ER 90 006) regarding a manual reactor trip due to full closure of a feedvater isolation valve during partial stroke
testing.
This event did not have any adverse impact on the health' and safety
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of the public.
If you should have any questions on this matter, please contact
Mr. S. M. Head at (512) 972 7136 or myself at (512) 972 7921.
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Warren H. Kinsey,
Vice President
Noclear Generation
SMH/aap
Attachment: LER 90 006 (South Texas / Unit'1)
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A Subsidiary of Houston industries incornotated
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Houston 1.lghtin & Power Cdtnpany
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South Teiss Project Electric (4nerating Station
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cc:
Regional Administrator, Region IV
Rufus S. Scott
Nuclear Regulatory Commission
Associate General Counsel
,
611 Ryan Plaza Drive Suite 1000
Houston Lighting & Power Company
Arlington, TX 76011
P. O. Box 61867
Houston, TX 77208
Coorge Dick, Project Manager
U.S. Nuclear Regulatory Commission
Washington, DC 20555
Records Center
1100 circle 75 Parkway
J. 1. Tapia
Atlanta, CA 30339 3064
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Senior Resident Inspector
c/o U. S. Nuclear Regulatory
Dr. Joseph M. Hendrie
commission
50 Be11 port Lane
P. O. Box 910
Be11 port, NY 11713
Bay City. TX 77414
D. K. Lacker
J. R. Novman, Esquire
Bureau of Radiation Control
Newcan & Holtzinger, P.C.
Texas Department of Health
1615 L Street, N.W.
1100 West 49th Street
Washington, DC 20036
Austin, TX 78704
D. E. Ward /R. P. Verret
Central Power & Light Company
P. O. Box 2121
Corpus Christi, TX 78403
J. C. lanter
Director of Generation
City of Austin Electric Utility
721 Barton Springs Road
Austin, TX 78704
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R. J. Costello/M. T. Hardt
City Public Service Board
P. O. Box 1771
San Antonio, TX 78296
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Revised 12/15/89
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L4/NRC/
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LICENSEE EVENT REPORT (LER)
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South Texas, Unit 1
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'""' Manual Reactor Trip Dae to Full Closure og a
Feedwater Isolation Valve During partial Stroke Testint
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Supervising Licensing Engineer
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On July 30.1990, Unit 1 was in Mode 1 at 1004 power. At approximately 1946,
Feedwater Isolation Valve 1A fully closed during a partial stroke surveillance
test. The resultant loss of feedwater flow caused a decrease in steam
generator level and the reactor was manually tripped. The unit was stabilized
with the exception of level in Steam Cencrator 1A which did not recover. due to
a mispositioned recirculation test valve in the Train A Auxiliary Feedwater
System (AFV). The recirculation test valve us returned to the required
position and Steam Cenerator 1A level was recovered. The Teedvater Isolation
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Valve closure was caused by a technician inadvettently contacting the wrong
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terminal with a test jumper. The cause of the miepositioned recirculation
test valve could not be conclusively established; hswever it is likely that
the valve was not correctly repositioned during a sur >eillance test prior to
the event, and this error was nct discovered due to a lack of adequate
independent verification.
Corrective actions include:
issuance of training
bulletins concerning use of junpers; evaluation of alternative designs to
obviate the need to perform the partial stroke test with jumpcies; and.
issuance of a memorandum to operations personnel to reenforce the requirements
pertaining to independent verification.
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lUCENSEE EVENT REPORT (LER) TEXT CONTINUATION l
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DESCRIPTION OF EVENT:
on July 50,1990, Unit 1 was in Mode 1 at 1006 power. At 1946, Feedwater
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Isolation Valve (WIV) 1A fully closed during performance of a partial stroke
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surveillance test.
Steam Cenerator (SC) 1A level began decreasing and the
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reactor was manually tripped since an automatic reactor trip was imminent due
to low steam generator water level. The turbine tripped, Feedwater Isolation
occurred on low Reactor Coolant System average temperature, and Auxiliary
Feodwater (AW) flow initiated on low. low steam generator level as expected.
No other Engineered Safety Feature actuations occurred during this event.
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Emergency Operating Procedures were entered and the plant was stabilized with
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the exception that level did not recover in Steam Generatcr 1A as expected.
Operations personnel determined that a recirculation valve on the
'A'
train of
AW was nispositioned causing the flow to return to the Auxiliary Feedwater
Storage Tank (AWST). The recirculation valve was repositioned to recover SC
1A level. The NRC was notified of this event at 2135 hours0.0247 days <br />0.593 hours <br />0.00353 weeks <br />8.123675e-4 months <br />.
The WIV's are hydraulically operated with a nitrogen charge in the upper
cylinder. The valve is closed by opening one or both of two solenoid valves
in parallel which dumps hydraulic fluid back to a reservoir; this allows the
nitrogen charge to drive the valve closed. The partial stroke test verifies
that both solenoids open and the WIV closes to the 906 position. Solenoid
positio. is sensed by reed switches connected to the test circuitry. The
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solenoids and reed switches are located within the valve yoke and are
difficult to maintain at power.
If a reed si' itch is not functioning
cort ectly, as is the case with WIV 1A, an 'a.' ternate * partial stroke test
prot edure using jumpers is employed which allovs testing each solenoid
individually.
The 'siternate" partial stroke test procedure specit'?es use of alligator clips
to connect jumpers.
Prior to the event, a technician had installed the
jumpets in a relay cabinet as specified in the test procedure. However, prior
to actaally conducting the stroke test, the alligator clip of a landed jumper
slipped off and Cell to the floor. In the process of relanding the jumper,
contact was inadvertently made with an adjacent terminal, causing WIV 1A to
close.
During the post. trip recovery process, Operations personnel observed that
Steam Generator 1A level continued to decrease even though the associated AW
flow was approximately 600 gpa. The
'A' train AW pump was secured af ter
receiving a low discharge pressure alars. Cross connect valves were opened in
an attempt to feed Steam Cenerator 1A from a different AW train; however,
this proved unsuccessful.
Subsequently, the "A*
train recirculating test
valve was discovered to be locked open instead of being in the required
' locked closed' position. This condition diverted AW flow back to the AWST,
thereby preventing AW flow from entering Steam Generator 1A. The
recirculation test valve was repositioned and AW flow was established to
Steam Generator 1A.
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UCENSEE EVr.dT REPORT RERI TEXT CONilNUATION
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An invest 15ation determined that the last known time the recirculation valve
(
was manipulated was on July 26 during a monthly AW inservice pump test.
There is no record of any other activities that would have caused the valve to
,
be operated between July 26 and the date of the event. There is also no
i
evidence of maliciousness or tampering. However, it was determined that a
less than adequate independent verification was performed on the part of the
!
two operators assigned to manipulate the valve during the July 26 test.
Independent verification is the act of checking a condition, such as valve
position, separately from establishing the condition or component position.
Contrary to this philosophy, it was determined that both operators were
present at the valve at the time it was to be closed, thus violating the
intent of independent verification.
It has been concluded, therefore, that
the valve was apparently not correctly positioned by one operator (possibly
',
due to the orientation of the valve), and that this condition was not
discovered by the second operator due to a lack of adequate independent
,
verification.
CAUSE OF EVENT:
The direct cause of the manu31 reactor trip was a failed closed feedwater
isolation valve. The failed. closed feedwater isolation valve was caused by a
technician inadvertently contacting the wrong terminal with a test jumper. A
f
contributing factor was that the test procedure specified use of alligator
clips, which are prone to fall off the tensinals used during the test.
Additional contributing factors are that the WIV's solenoid valve reed
switches were not functioning, and the design is such that they are difficult
to maintain at power. With the reed switches not functioning, a successful
partial stroke test could not be performed without the use of jumpers.
The cause of the mispositioned AW recirculation valve could not be
conclusively established; however, it is likely that the valve was not
correctly positioned by one operator'and that this error was not discovered
due to a lack of adequate independent verification on the part of a second
operator.
ANALYSIS OF EVENT:
Reactor Protection System and Engineered Safety Features actuations are
reportable pursuant to 10Cnt50.73.(a)(2)(iv). All safety systems responded as
expected, with the exception of Auxiliary Feedwater System Train A.
Steam
Cenerator 1A level decreased significantly and remained low for approximately
one hour because AW flow was diverted back to the AWST due to a locked.open
recirculation test valve. A minimum wide range level of 31% was achieved at
approximately 50 minutes after the trip. An adequate heat sink was maintained
during the event by maintaining AW flow to
"B",
'C',
and
'D'
steam
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Technical Specification 3.7.1.2 requires at least four independent steam
l
getierator auxiliary feedwater pumps and associated flow paths to be operable
in Modes 1, 2, and 3 including three motor. driven and one turbine driven
pumps. Under the worst case Design Basis Accident scenarios, including single
i
failure, one train of A W is adequate to cool the RCS even if the
'A'
train of
.
l
AW is out of service. In recognition of this fact, the Technical
>
I
Specification allows an unlimited outage time for the
'A' train of AN with
the stipulation that action be immediately initiated to return the
'A'
train
'
to service. Upon discovering the cause of the inoperability of
'A'
train,
action was immediately taken to return the train to service. Since the Design
Basis Accident can be adequately mitigated with the
'A' AW train
out of service, this particular event had mi0imal safety consequences.
If the mispositioned valve had occurred on one of the other A W trains, the
worst case scenario is a main ateam line break ar a feedwater line break that
is assumed to remove the cooling capacity of the AW train on the affected
For these events the following cases were analyzed:
Train B Valve Mispositioned:
For this sconario, the worst case
situation would arise if the break were located in the
'C' train. The
AW design is such that if the single failure is assumed to be in the
'A' actuation train of the Solid State Protection System, then neither
the
'A' or
'D' trains of A W would be automatically actuated. However,
one of the early steps in performance of the F.mergency Operation
Proceduros is verification of AW actuation. AW flow would be manually
initiated by control room personnel, thus providing cooling flow to the
Train C Valve Mispositioned: This scenario is similar to the
'B'
train
scenario described above.
Train D Valve Hispositioned:
For this case, the
'D' train is,
.
unavailable due to the valve being mispositioned.
In addition, one
train of AW is assumed unavailable due to the break and one train of
AW is unavailable due to a single failure,
i.e., a standby diesel
generator failed to start under loss of alternating current. This would
still leave one train of AW available to provide cooling to the RCS.
Since it is possible to readily provide flow to at least one steam generator
with a locked open recirculation valve on any AW train, the safety
consequences of a locked open valve on any one AW train are minimal.
The above cases have been analyzed in the Auxiliary Feedwater System
Reliability Evaluation provided in Appendix 10A of the Updated Final Safety
Analysis Report. Specifically, this reliability study included the assumption
t. hat a recirculation valve would be mispositioned with a frequency of 1 in 200
manipulations. STP experience is consistent with this assumption.
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COPJtECTIVE ACTI@
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The following corrective actions are being taken as a result of this event:
A training bulletin will be issued by September 12, 1990 to 14,C
1)
Technicians which will discuss this event and reemphastae individual
responsibilities in regard to critical testing manipulations.
The partial stroke surveillance test procedures as well as other
2)
surveillance procedures that use jumpers will be reviewed to develop
enhancements that can minimize the potential for reactor trips or
Engineered Safety Teatures actuations. This review will be
completed by December 7,1990.
An evaluation will be performed to determine if an alternative
3)
design can be developed which would allow for partial stroke testing
of the IVIVs without the use of jumpers. This evaluation will be
-
completed by January 31, 1991.
4) Valve lineups were performed immediately and independently verified
on various valves in the major flow paths in the following
safety.related systems for both Unit 1 and Unit 2: Auxiliary
j
Teedwater, Containment Isolation, Main peedwater, Containment Spray,
l
and Safety injection. Valve lineups were also performed on
accessible Engineered Safety Teature valves in the tecked Valve
Program and Standby Readiness 1.ineups were performed on the Standby
Diesel Generators on both Unit 1 and Unit 2.
No deficiencies were
identified during these lineup checks.
5) The operators involved in the ATV valve manipulation were counseled
. as to the appropriate methods for performing independent
verification.
6) A memorandum has been forwarded to the operating staff reemphasizing
the need to 'self verify * all sanipulations to ensure that the
desired result has in fact occurred.
7) A memorandum has been forwarded to the operating staff reemphasizing
the importance of and requirements for independent verification and
the proper methods of verifying valve positions.
8) This event will be included in operator continuing training, with
emphasis placed on the ramifications of misaligning the Auxiliary
Teedwater System and the requirements for Independent Verification.
This action will be completed by November 30, 1990,
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LICENSEE EVENT REFORT ILER) TEXT CONTINUATION
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ADDITIONAL INftRMATION:
There has been a previously reported event (IDt 2 89 019) concerning a reactor
i
trip caused by a WIV failing closed; however, the event was not associated
,
with a test jumper but was caused by a failure in the test circuitry.
.
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